Serial (RS-232) Connector Technical Information

Pin No.

Description

1

Not used

2

RXD (receive data) input to the printer

 

 

3

TXD (transmit data) output from the printer

4

DTR (data terminal ready) output from the printer -- controls when

the host may send data

 

5

Chassis ground

 

 

6

DSR (data set ready) input to the printer

 

 

7

RTS (request to send) output from the printer -- always in the

ACTIVE condition when the printer is turned on

 

8

Not used

 

 

9

5 V @ 0.75 A fused

 

 

NOTES: The maximum current available through the serial and/or parallel port is not to exceed a total of 0.75 Amps.

When XON/XOFF handshaking is selected, data flow is controlled by the ASCII control codes DC1 (XON) and DC3 (XOFF). The DTR control lead will have no effect.

Interconnecting to DTE Devices

The printer is configured as data terminal equipment (DTE). To connect the printer to other DTE devices (such as the serial port of a personal computer), use an RS-232 null modem (crossover) cable.

Figure 38 shows the required cable connections.

Interconnecting to DCE Devices

When the printer is connected via its RS-232 interface to data communication equipment (DCE) such as a modem, a STANDARD RS-232 (straight-through) interface cable must be used. Figure 39 shows the connections required for this cable.

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